Ratchet buckle



March 30, 1965 Filed Nov. 4, 1963 E. PRETE, JR 3,175,806

RATCHET BUCKLE 5 Sheets-Sheet 1 .-J5 r---+- "-1 a L 42 20 20/ a 6 .1

I36 3& 10

March 30, 1965 PRETE, JR 3,175,806

RATCHET BUCKLE Filed Nov. 4, 1963 5 Sheets-Sheet 2 March 30, 1965 E.PRETE, JR 3,175,806

RATCHET BUCKLE Filed Nov. 4, 1963 5 Sheets-Sheet 3 March 30, 1965 E.PRETE, JR 3,175,806

RATCHET BUCKLE Filed Nov. 4, 1965 5 Sheets-Sheet 4 March 30, 1965 PRETE,JR 3,175,806

RATCHET BUCKLE Filed Nov. 4, 1963 5 -Sheet 5 United States Patent3,175,806 RATCHET BUCKLE Ernest Prete, J12, Sherman Oaks, Calif.,assignor to Browndline Corporation, El Segundo, Calif., a corporation ofCalifornia Filed Nov. t, 1963, Ser. No. 321,065 '11 Claims. (Cl.254-164) This invention relates to a ratchet type buckle for tensioningan elongated flexible member such as a strap, rope or cable.

While the invention is widely applicable for its purpose, it has beeninitially embodied in a buckle for tensioning a strap to tie down cargoin an aircraft. This particular embodiment of the invention is disclosedherein and will provide adequate guidance for those skilled in the artwho may have occasion to apply the invention to other specific purposes.

A buckle for tying down a cargo strap is typically formed with a hook toengage, for example, a shackle on the floor space or to engage a loop onthe end of a strap. One end of the strap that is to be tensioned by thebuckle is connected to a spool on the buckle to be wound thereon and theother end of the strap typically carries a hook member for engagementwith a second on the floor. With the buckle connected with one shackleand the strap hook engaging the other shackle, a pawl and ratchetmechanism that is incorporated into the construction of the buckle ismanually operated to wind in the strap and thereby place the strap underefi'ective tension.

Such a ratchet mechanism conventionally includes ratchet teeth carriedby the spool and a spring-pressed holding pawl to prevent reverserotation of the spool together with a spring-pressed driving pawl torotate the spool in the winding direction. As heretofore constructed,such a tie-down strap buckle is a complicated device having numerousworking parts including a plurality of springs. Obviously the morecomplicated the mechanism the higher the cost and the greater thepossibility of malfunction or failure. The broad object of the presentinvention is to provide a simpler tie-down buckle of fewer working partsfor higher reliability as well as lower cost.

Simplicity is achieved in a number of different ways. For example, theusual spring-pressed holding pawl is eliminated entirely by using afixed lug means to serve the function of a holding pawl and by mountingthe spool in a floating manner, the arrangement being such that thetension of the strap urges the spool into engagement with the fixedholding lug. Thus the strap itself provides the yielding force that isusually provided by a special spring. Both reliability and simplicityare served by eliminating the spring and obviously a fixed stud means toserve the function of a holding pawl is more reliable than a pivotallymounted and spring-pressed pawl.

Another example of achieving simplicity is in providing dual functionsfor the usual spring-pressed driving pawl means. In addition to servingits usual purpose, the spring-pressed driving pawl means also has thefunction of serving as a latch means for locking the ratchet mechanismagainst inadvertent release operation while the buckle is in service.

Still another example is found in the multiple functions of an operatinghandle which is oscillated to operate the ratchet mechanism. One of theadded functions of the operating handle is to serve at its normalretracted position as means to prevent the spool from shifting out ofits position of engagement with the fixed holding stud means. Another ofits added functions is to serve, when desired, to provide cam action toshift the spool out of engagement with the fixed holding stud meansthereby to release the spool for rotation in the unwinding direction.

Reduction in weight is of special importance in an aircraft. Theinvention minimizes weight and at the same time keeps down cost byproviding a design which is constructed primarily of sheet metal partsthat can be fabricated by punch press operations. The remaining partsare made of tubing stock and rod stock.

The features and advantages of the invention may be understood from thefollowing detailed description and the accompanying drawing.

In the drawing, which is to be regarded as merely illustrative:

FIG. 1 is a perspective view of the presently preferred embodiment ofthe invention as seen from above;

FIG. 2 is a bottom plan view of the device;

FIG. 3 is a side elevational view of the device in its normal positionholding a strap under tension to tie down cargo;

FIG. 4 is a similar view of the device with the operating handleunlatched in preparation for manual manipulation to tighten the strap;

FIG. 5 is a similar view showing the operating handle at an intermediatepoint in its actuating stroke to tighten the strap;

FIG. 6 is a similar view showing the operation handle at the end of itsactuating stroke; and

FIG. 7 shows how the operating handle may be shifted beyond the range ofits actuating stroke for the purpose of releasing the spool forunwinding rotation to loosen the strap.

Referring first to FIGS. 1, 2 and 3, the principal parts of the ratchetbuckle include: a buckle body, generally designated 10, which forms ahook 12 that may, for example, engage a fixed shackle 14 in the floor ofan air craft; a spool generally designated 15 for winding up one end ofa strap 16, the spool being provided with ratchet teeth 18 at itsopposite ends; two fixed holding lugs 20 carried by the buckle body toengage the ratchet teeth to prevent reverse rotation of the spool; anoperating handle 22 for reciprocation to drive the spool in the windingdirection; and a retractable driving pawl member 24! carried by theoperating handle for engagement with the ratchet teeth.

In this particular embodiment of the invention, the buckle body 16 ismade of two heavy sheet metal stampings which form the two sides of thebody and which converge together to form the hook 12. In the region ofthe hook 12 the two stampings are held together by rivets 25 and 26 andthe two spaced portions of the stampings that form the opposite sides ofthe body are interconnected by two cross rods 28 and 3t). The cross rod28 carries a spacer sleeve 32, and is connected to the two stampings byextending through bores in the two stampings respectively with the outerends of the cross rods peened or staked. As best shown in FIGS. 1 and 4,the converging portions of the two stampings are shaped to form a pairof latch hooks 35 for cooperation with the driving pawl 24 to releasablyhold the operating handle 22 in its normal retracted position shown inFIGS. 1-3.

As may be seen in FIG. 2, each of the two holding lugs 20 is the reducedinner end of a fitting mounted in the corresponding sheet metalstamping. The outer enlarged ends of the fitting form external lugs 36on the opposite outer sides of the buckle body, which lugs may be termedcamming lugs since they cooperate with the handle 22 in a carnmingoperation, as will be explained.

The spool 15 may be of the construction shown wherein two opposite disks33 form the flanges of the spool and are rigidly interconnected by apair of transverse rods 40. The rods til have reduced ends which extendthrough the two disks 3% and are staked at their outer ends. Two outerratchet disks forming the ratchet teeth 18 are mounted on the oppositeends of the spool and are secured by staking the ends of the two rodsthat are concealed in the two tubes 40. The spool is rotatably mountedon the buckle body by two trunnions 42 that extend through correspondingslots 44 (PEG. 3) in the two opposite sides of the buckle body, theouter ends of the two trunnions being secured to the operating handle22. In the construction shown, the two trunnions 4-2 extend throughcorresponding bores in the handle 22 and through washers 45 on the outerfaces of the handle, the ends of the trunnions being peened or stakedfor retention by the washers.

As indicated in FIG. 3, the two slots 44- in the opposite sides of thebuckle body are in approximate alignment with the two previouslymentioned inner holding lugs and external camrning lugs 36. When thestrap 16 is wound onto the spool 15 in the manner shown in PEG. 3 andthe strap is under tension, the two slots 44 are oriented at an acuteangle relative to the general direction of the tensioned strap with theconsequence that the tension of the strap urges the trunnions 4;. to theends of the two slots that are closest to the holding lugs 2t and thecamming lugs 36. Thus the tension in the strap 16 provides a yieldingforce that is equivalent to spring force to urge the ratchet teeth 18 ofthe spool into holding engagement with the two holding lugs 20 as may beseen in FIG. 4.

As may be seen in FIG. 1, the handle 22 is a U-shaped piece of heavysheet metal with its two lugs connected respectively to the twotrunnions 42 for pivotal movement of the handle about the axis of thespool. When the handle 22 is in its normal latched position shown inFIGS. 1 and 3, two arcuate locking fingers 46 formed on the oppositesides of the handle engage corresponding locking lugs 48 on the bucklebody to lock the spool 15 in its position of holding engagement with thetwo holding lugs 20. The locking lugs 43 may be provided as shown bysimply lancing and offsetting the sheet metal of the buckle body.

The operating handle 22 is further formed with two arcuate cam edges onits opposite sides that are eccentric relative to the two trunnions 42and are adapted for camming action against the corresponding camminglugs 36 to shift the spool out of holding engagement with the twoholding lugs 26. The cam action occurs when the handle 22 is swungcounterclockwise from the position shown in FIG. 6 to the extremeposition shown in FIG. 7.

The driving pawl 24 may be in the form of a fiat piece of heavy sheetmetal having two opposite guide cars 52 that slidingly extend intocorresponding guide slots 54 in the opposite sides of the operatinghandle 22. The outer end of the driving pawl 24 is formed with alongitudinal guide finger 55 that slidingly extends through a guide slot56 in the end of the operating handle.

The inner end of the driving pawl 24 is formed with two pawl fingers 58that straddle the spool 15 for the purpose of engaging the ratchet teeth18 to drive the spool in the direction to wind in the strap 16. Thedriving pawl 24 may be biased into engagement with the spool teeth 18 bymeans of a compression spring 60 that surrounds the guide finger 55under compression between the driving pawl and the operating handle 22.

To make it convenient to retract the driving pawl 24 manually, the sheetmetal of the driving pawl may be formed with a large aperture 62 whichdefines a T-shaped handle 64 that is bent outward from the plane of thedriving pawl as shown. The edges formed by the aperture 62 provide twospaced latching shoulders 65 for releasable engagement with thepreviously mentioned latch hooks of the buckle body. It is to be notedthat the spring 60 biases the driving pawl 24 for releasable engagementwith the latch hooks 35 as well as for releasable engagement with theratchet teeth 18 of the spool.

Operation FIGS. 1, 2 and 3 show the ratchet buckle in service holdingthe strap 16 under tension for the purpose of tying down a load. Thefact that the arcuate locking fingers d6 engage the locking lugs 48 atthe normal retracted position of the operating handle 22 and the factthat the operating handle is held in its locking position by engagementof the driving pawl 24 With the two latch hooks 35 provide positiveassurance that the spool 15 will not shift out of engagement with theholding lugs 26.

In preparation for employing the operating handle 22 to place the strap16 under tension, the driving pawl 24 is manually retracted out ofengagement with the latch hooks 35 against the opposition of the spring6% and then with the handle lifted slightly the driving pawl is releasedto return to its normal position as shown in FIG. 4. In FIG. 4, thedriving pawl 24 rests on the two latch hooks 35 so that the two latchhooks serve as a stop to limit clockwise rotation of the operatinghandle 22.

The spool 15 is rotated in the direction to wind in the strap 16 byswinging the operating handle 22 counterclockwise from the positionshown in FIG. 4 to the position shown in FIG. 6. Early in thisstrap-tensioning stroke of the operating handle 22, the driving pawl 24engages ratchet teeth 18 of the spool 15 to rotate the spoolcounterclockwise with the consequence that a pair of ratchet teeth a inFIG. 5 cam against the two holding lugs 20 to shift the spool along thetwo inclined slots 44 in opposition to the tension of the strap 16. Whenthe operating handle 22 is swung counterclockwise beyond the positionshown in FIG. 5 to bring the two teeth 18a past the two holding lugs 20,the spool drops back in the two parallel slots 4 to the position shownin PEG. 6 with the abrupt shoulders of the two teeth 18a in holdingengagement with the two holding lugs 20. Thus the counterclockwisemovement of the operating handle 22 from the position shown in FIG. 4 tothe position shown in FIG. 6 advances the rotation of the spool by atleast one ratchet tooth in the strap-tightening direction. Thereciprocation ot the handle 22 is repeated until the strap is undersufficient tension to hold down the cargo, the driving pawl 24 ismanually retracted to permit the handle to be swung back to its normalposition and then the driving pawl is released for engagement with thetwo latch hooks 35 as shown in FIGS. 1 and 3.

When it is desired to release the spool 15 for reverse rotation toloosen the tensioned strap 16, the operating handle 22 is released fromthe two latch hooks 35 by manual retraction of the driving pawl 24 andthe driving pawl is held in its retracted position to prevent engagementwith the ratchet teeth 18 while the operating handle is swungcounterclockwise from the position shown in HG. 4 to the extreme releaseposition shown in FIG. 7. The release position is beyond thestrap-tensioning stroke of the handle as may be seen by comparing FIG. 7with FIG. 6. When the operating handle 22 in its counterclockwisemovement reaches the position shown in FIG. 6, the two arcuate cam edges50 of the operating handle come into operating contact with the twocorresponding cam lugs 36 and the further counterclockwise movement ofthe operating handle from the position shown in FIG. 6 to the positionshown in FIG. 7 causes the two cam edges to cooperate with the two camlugs 36 to shift the handle and thereby shift the spool 15 along the twoparallel slots 44 until the ratchet teeth 18a in FIG. 6 escape from theholding lugs 29 to free the spool for reverse rotation.

My description in specific detail of the selected embodiment of theinvention will suggest various changes, substitutions and otherdepartures from my disclosure within the spirit and scope of theappended claims.

I claim:

1. In a device of the character described for winding in a flexiblemember, the combination of:

a body;

a spool for attachment to the flexible member and adapted to wind in theflexible member in a given general direction, the spool having ratchetteeth; means to rotate the spool in its winding direction; blockingmeans fixedly mounted on the body to block unwinding rotation of thespool,

the spool being both rotatably and fioatingly mounted on the body forrotation relative thereto and for translation relative thereto along agiven path into and out of engagement with the blocking means, saidgiven path being oriented at less than 90 from the given generaldirection to cause the spool to be biased into engagement with theblocking means by resistance of the flexible means to the windingoperation of the spool; and

means to shift the spool along said path away from the blocking means torelease the spool for unwinding rotation.

2. In a ratchet-type buckle of the character described for tensioning anelongated flexible member, the combination of:

a buckle body adapted for suitable anchorage, the body including twointerconnected opposite side members;

a spool adapted for connection with one end of the flexible member towind in the flexible member in a given general direction relative to thespool thereby to tension the flexible member, the spool having ratchetteeth;

manually operable means to rotate the spool in the winding direction;

blocking means fixedly mounted on the body to engage the ratchet teethto block unwinding rotation of the spool;

means rotatably mounting the spool on the body with freedom fortranslation of the spool along a given path, the path being orientedrelative to said general direction and the blocking means beingpositioned relative to the path and relative to the general direction tocause the tension in the flexible member to urge the journaling meansalong the path toward the blocking means to a blocking position at whichthe blocking means engages the ratchet teeth to prevent unwindingrotation of the spool; and

manually operable means to shift the spool along said path away from theblocking means to release the spool for unwinding rotation.

3. A combination as set forth in claim 2, in which the means to rotatethe spool comprises:

ratchet means and a manually operable handle for the ratchet means, thehandle being movable from a normal retracted position to an advancedposition; and

means responsive to movement of the handle to its normal position tolock the spool against translation at the position of the spool at whichthe spool engages said blocking means.

4. In a ratchet-type buckle of the character described for tensioning anelongated flexible member, the combination of:

a buckle body adapted for suitable anchorage, the body including twointerconnected opposite side members;

a spool adapted for connection with one end of the flexible member towind in the flexible member in a given general direction relative to thespool thereby to tension the flexible member, the spool having ratchetteeth;

manual means swingable about the axis of the spool between a normalposition and an advanced position;

pawl means movably mounted on the manual means and biased to engage theteeth of the spool to rotate the spool in the winding direction inresponse to movement of the manual means towards its advanced position;

blocking means fixedly mounted on the body to engage 6 the ratchet teethto block unwinding rotation of the spool;

means rotatably mounting the spool on the body with freedom fortnanslationi of the spool along a given path, the path being orientedrelative to said general direction and the blocking means beingpositioned relative to the path and relative to the general direotion tocause the tension in the flexible member to urge the journaling meansalong the path towards the blocking means to a blocking position atwhich the blocking means engages the ratchet teeth to prevent unwindingrotation of the spool; and

manually operable means to shift the spool along said path away from theblocking means to release the spool for unwinding rotation.

5. A combination as set forth in claim 4 which includes means toreleasably latch the manual means at its noranal position.

6. A combination as set forth in claim 5 which includes fixed means onthe body engage-able by the manual means at its normal latched positionto lock the j ournaling means in its blocking position.

7. A combination as set forth in claim 4, in which the manually operablemeans to shift the spool along the path away from the blocking meanscomprises fixed means on the body together with cam means carried by themanual means and cooperative with the fixed means to shift thejournaling means.

8. In a ratchet-type buckle of the character described for tensioning anelongated flexible member, the combination of:

a buckle body adapted for suitable anchorage, the body including twointerconnected opposite side members;

a spool adapted for connection with one end of the flexible member towind in the flexible member in a given general direction relative to thespool thereby to tension the flexible member, the spool having ratchetteeth;

blocking means fixedly mounted on the body to engage the ratchet teethto block unwinding rotation of the spool;

two parallel slots in the two side members respectively;

axial means carried by the spool and extending therefrom in oppositeaxial directions through said two slots respectively to journal thespool for rotation relative to the body and the permit bodily shift ofthe spool along the two slots relative to the blocking means,

the two slots and the blocking means being oriented relative to thegeneral direction to cause the tension in the flexible means to urge thespool towards engagement with the blocking means;

manual means mounted on said axial means to swing about the axis thereofbetween a normal retracted position and an advanced position;

pawl means movably mounted on said manual means and biased to engage theteeth of the spool to rotate the spool in the winding direction inresponse to movement of the manual means towards its advanced position;

means to neleasably latch the manual means at its normal position; and

means to shift re axial means along the two slots away from the blockingmeans to release the spool for unwinding rotation.

9. A combination as set forth in claim 8, which includes means toreleasably latch the axial means against shifting of the spool out ofengagement with the blocking means.

10. In a ratchet-type buckle of the. character described for tensioningan elongated flexible member, the combination of:

a buckle body adapted for anchorage, the body including twointerconnected opposite side members;

a spool adapted for connection with one end of the flexible member towind in the flexible member in a given general direction relative to thespool thereby to tension the flexible member, the spool having ratchetteeth;

blocking means fixedly mounted on the body to engage the ratchet teethto block unwinding rotation of the spool;

two parallel slots in the two side members respectively;

axial means carried by the spool and extending therefrom in oppositeaxial directions through said two slots respectively to journal thespool for rotation relative to the body and to permit bodily shift ofthe spool along the two slots relative to the blocking means forreleasable engagement of the teeth of the spool with the blocking means,

the two slots and the blocking means being oriented relative to thegeneral direction to cause the tension in the flexible means to urge thespool towards engagement with the blocking means;

manual means mounted on the axial means to swing about the axis thereoffrom a normal retracted position to a first advanced position and beyondthe first advanced position to a second advanced position;

pawl means movably mounted on the manual means and biased to engage theteeth of the spool to rotate the spool in a winding direction inresponse tothe movement of the manual means from its normal retractedposition to its first advanced position;

latch means fixedly mounted on the body adjacent the normal retractedposition of the manual means for engagement by the pawl means to latchthe manual means at its normal retracted position, the pawl means beingretractable to move past the latch means;

first fixed means on the body;

cam means united with the manual means for movement therewith, the cammeans being eccentric relative to the axial means to act against thefirst fixed means to shift the spool along the two slots out ofengagement with the blocking means, the cam means being located to beeffective in response to movement of the manual means from its firstadvanced position to its second advanced position whereby the spool maybe released for reverse rotation by retracting the pawl means and movingthe manual means to its second advanced position;

second fixed means on the body; and

latch means on the manual means to engage the second fixed means at thenormal retracted position of the manual means to prevent the axial meansfrom moving along the two slots thereby to prevent release of the spoolfrom the blocking means as long as the manual means is in its normalretracted position.

11. In a ratchet-type buckle of the character described for tensioningan elongated iiexible member, the combination of:

a buckle body adapted for anchorage, the body including twointerconnected opposite side members having slots therein;

a spool adapted for connection with one end of the flexible member towind in the flexible member in a given general direction relative to thespool thereby to tension the flexible member, the spool having ratchetteeth;

blocking means fixedly mounted on the buckle body to engage the ratchetteeth to block unwinding rotation of the spool;

axial means carried by the spool and extending therefrom in oppositeaxial directions through the two slots respectively to journal the spoolfor rotation relative to the body and to permit bodily shift of thespool along the two slots relative to the blocking means for releasableengagement of the teeth of the spool with the blocking means,

the two slots and the blocking means being oriented relative to thegeneral direction to cause the tension in the flexible means to urge thespool towands engagement with the blocking means;

manual means mounted on the axial means to swing about the axis thereoffrom a normal retracted position to a first advanced position and beyondthe first advanced position to a second advanced position;

pawl means m-ovably mounted on the manual means and biased to engage theteeth of the spool to rotate the spool in, the winding directioninresponse to movement of the manual means from its normal position to itsfirst advanced position;

cooperative means on the manual means and the buckle body respectivelyto lock the spool in engagement with the blocking means when the manualmeans is in its normal position;

cooperative means on the manual means and the buckle body respectivelyto latch the manual means at its normal position; and

cooperative means on the manual means and the buckle body respectivelyto move the spool out of engagement with the blocking means in responseto movement of the manual means from its firs-t advanced position to itssecond advanced position.

References Cited by the Examiner UNITED STATES PATENTS 2,658,722 11/53Coiling 254-167 2,719,696 10/55 Palka 254--146 2,874,431 2/59 Elsncr24-71.2 2,993,680 7/61 Davis.

DONLEY J. STOCKING, Primary Examiner.

BOBBY R. GAY, Examiner.

1. IN A DEVICE OF THE CHARACTER DESCRIBED FOR WINDING IN A FLEXIBLEMEMBER, THE COMBINATION OF: A BODY; A SPOOL FOR ATTACHMENT TO THEFLEXIBLE MEMBER AND ADAPTED TO WIND IN THE FLEXIBLE MEMBER IN A GIVENGENERAL DIRECTION, THE SPOOL HAVING RATCHET TEETH; MEANS TO ROTATE THESPOOL IN ITS WINDING DIRECTION; BLOCKING MEANS FIXEDLY MOUNTED ON THEBODY TO BLOCK UNWINDING ROTATION OF THE SPOOL, THE SPOOL BEING BOTHROTATABLY AND FLOATINGLY MOUNTED ON THE BODY FOR ROTATION RELATIVETHERETO AND FOR TRANSLATION RELATIVE THERETO ALONG A GIVEN PATH INTO ANDOUT OF ENGAGEMENT WITH THE BLOCKING MEANS, SAID GIVEN PATH BEINGORIENTED AT LESS THAN 90* FROM THE GIVEN GENERAL DIRECTION TO CAUSE THESPOOL TO BE BIASED INTO ENGAGEMENT WITH THE BLOCKING MEANS BY RESISTANCEOF THE FLEXIBLE MEANS TO THE WINDING OPERATION OF THE SPOOL; AND MEANSTO SHIFT AND SPOOL ALONG SAID PATH AWAY FROM THE BLOCKING MEANS TORELEASE THE SPOOL FOR UNWINDING ROTATION.